IgG subclass deficiency in children with recurrent bronchitis

Transient low IgG4 levels cause recurrent wheezing requiring multiple hospitalizations in infancy

OBJECTIVES

To investigate whether the immunoglobulin G (IgG4) subclass is associated with recurrent wheezing and/or asthma in infants.

SUBJECTS AND METHODS

From April 2015 to March 2016, 77 infants under 3 years old who attended our hospital were enrolled in four groups (Group 1, controls; Group 2, infants with recurrent wheezing and multiple hospitalizations despite starting inhaled corticosteroids [ICS]; Group 3, infants with recurrent wheezing and without hospitalization after starting ICS; Group 4, allergic infants without wheezing). The relationship between IgG subclasses, especially IgG4, and recurrent wheezing resistant to ICS and requiring multiple hospitalizations in infants was examined.

RESULTS

The serum IgG, IgM, IgA, IgG1, IgG2, and IgG3 levels did not differ significantly among the four groups. The IgG4 level in Group 2 infants (3.1 ± 0.2 mg/dl) was significantly lower than in Groups 1, 3, and 4 (9.9 ± 8.0, 8.4 ± 6.1, and 23.4 ± 18.0 mg/dl). Of the 16 infants in Group 2, 10 could be followed to age 6 years. Nine of them had no recurrent wheezing at 6 years without medication. In addition, their IgG4 levels at age 6 years (16.1 ± 7.1 mg/dl) were significantly increased from those in infancy (3.0 ± 0.1 mg/dl).

CONCLUSION

A transient low IgG4 level in infancy might cause recurrent wheezing and/or asthmatic symptoms in infants, and it may be one of the types of early transient wheezing.

Pediatric recurrent respiratory tract infections: when and how to explore the immune system? (About 53 cases)

Recurrent respiratory tract infections are one of the most frequent reasons for pediatric visits and hospitalization. Causes of this pathology are multiple ranging from congenital to acquired and local to general. Immune deficiencies are considered as underlying conditions predisposing to this pathology. Our work is about to determine when and how to explore the immune system when facing recurrent respiratory infections. This was based on the records of 53 children hospitalized at the pediatrics unit of Hassan II University Hospital, Fez Morocco. Thirty boys and 23 girls with age ranging from 5 months to 12 years with an average age of 2 years were involved in this study. Bronchial foreign body was the main etiology in children of 3 to 6 year old. Gastro-esophageal reflux, which in some cases is a consequence of chronic cough, as well as asthma were most frequent in infants (17 and 15% respectively). Immune deficiency was described in 7.5% of patients and the only death we deplored in our series belongs to this group. Recurrent respiratory tract infections have multiple causes. In our series they are dominated by foreign body inhalation and gastroesophageal reflux, which in some cases is a consequence of a chronic cough. Immune deficiency is not frequent but could influence the prognosis. Therefore immune explorations should be well codified.

The role of OM-85 BV (Broncho-Vaxom) in preventing recurrent acute tonsillitis in children

OBJECTIVE

To evaluate the efficacy of an immunostimulant (bacterial lysate) Broncho-Vaxom in the management of children with recurrent acute tonsillitis.

METHODS

A 5-year retrospective cohort study of 177 children presenting with a diagnosis of recurrent acute tonsillitis. Patients' demographics and laboratory studies at presentation were retrieved. For patients given Broncho-Vaxom, we defined response as a decrease in the frequency of acute tonsillitis episodes after 3 months of therapy (partial: by ≤50% and total: by >50%). Patients showing response to Broncho-Vaxom were further followed until study-end or need for tonsillectomy.

RESULTS

The median age of patients was 4.5 years (range: 1-15 years) with 63.8% being males. 131 (74%) patients received Broncho-Vaxom as initial therapy, and 99 (75.6%) showed response (51.2% total and 24.4% partial response). A normal ESR level was the only predictor of total compared with no response (OR: 3.53, 95% CI: 1.03-12.07); while both normal ESR (OR: 7.15-times, 95% CI: 1.18-43.39) and normal CRP (OR: 12.66, 95% CI: 1.43-111.86) levels were independent predictors of total over partial response. None of the patients showing total response required tonsillectomy on long-term follow up while in those with partial response 34.4% required subsequent tonsillectomy (median follow-up: 9 months).

CONCLUSIONS

A considerable proportion of children receiving Broncho-Vaxom for recurrent acute tonsillitis show a decrease in the frequency of episodes in the short term, and very few patients eventually require tonsillectomy on long-term follow up.

Oral purified bacterial extracts in acute respiratory tract infections in childhood: a systematic quantitative review

BACKGROUND

Recurrent acute respiratory tract infections (ARTI) are a common problem in childhood. Some evidence suggests a benefit regarding the prevention of ARTI in children treated with the immunomodulator OM-85 BV (Bronchovaxom).

METHODS

We summarised the evidence on the effectiveness of the immunomodulator OM-85 BV in the prevention of ARTI in children. We searched randomised comparisons of oral purified bacterial extracts against inactive controls in children with respiratory tract diseases in nine electronic databases and reference lists of included studies. We extracted salient features of each study, calculated relative risks (RR) or weighted mean differences (WMD) and performed meta-analyses using random-effects models.

RESULTS

Thirteen studies (2,721 patients) of low to moderate quality tested OM-85 BV. Patients and outcomes differed substantially, which impeded pooling results of more than two trials. Two studies (240 patients) reporting on the number of patients with less than three infections over 6 month of follow-up in children not in day care showed a trend for benefit RR 0.82 (95% CI, 0.65-1.02). One out of two studies examining the number of children not in day care without infections over 4-6 month reported a significant RR of 0.42 (95% CI, 0.21-0.82) whereas the smaller, second study did not [RR 0.92 (95% CI, 0.58-1.46)]. Two studies reporting the number of antibiotic courses indicated a benefit for the intervention arm [WMD 2.0 (95% CI, 1.7-2.3)]. Two out of the three studies showed a reduction of length of episodes of 4-6 days whereas a third study showed no difference between the two groups.

CONCLUSION

Evidence in favour of OM-85 BV in the prevention of ARTI in children is weak. There is a trend for fewer and shorter infections and a reduction of antibiotic use.

Isolated IgG3 deficiency in children: to treat or not to treat? Case presentation and review of the literature

Immunoglobulin G3 (IgG3) subclass deficiency has received rather little attention thus far. In this report, the clinical and immunologic characteristics of six children with isolated IgG3 deficiency are discussed. The currently available literature on IgG3 deficiency is reviewed with specific emphasis on the peculiarities of the IgG3 subclass, the clinical relevance of IgG3 deficiency as well as the therapeutic options.

Montelukast in early childhood asthma. Predict value of IgG in clinical reply in children 2 to 5 years old?

BACKGROUND

According to current knowledge, asthma is basically an inflammatory process. Its causes and physiopathological mechanisms are various. The final result is a recurrent obstructive bronchial process, with sibilants and/or dypnea, which causes an upset in functional respiratory tests, among which the maximum respiratory peak flow meter diminished for the age, sex, and height of patient.

AIMS

Our aim is to evaluate if response to treatment with Montelukast has any link with immnuloglobin values (IgG, IgA, IgM, IgE) at start of treatment.

MATERIALS AND METHODS

Included in the study were 32 children, of whom 2 did not begin and 1 who did not provide personal data. There were 29 patients in total, 11 girls and 18 boys. Each made three visits: first where they were instructed, together with their parents, in how to manage the meter and where they received the peak flow meter, Vitalograph, and personal data sheet, where personal and family medical history were noted. The second visit was after 4 weeks, for a clinical assessment and the third visit after 8 weeks. The value register of the PEF would be made morning and night, noting the highest value of three measurements. IgG, IgA, IgM, IgA values were quantified before treatment began. The statistic package STATA 2001 was used in the treatment of data statistics.

RESULTS

Our between the value reached by the PEF after treatment and the IgG values at the beginning of treatment (0.712). In lesser measurement for IgA values (0.660). For each 100 mg/ml of increase in the value of IgG, an increase of 10 l/min in the PEF measurement before and following treatment with Montelukast was produced.

CONCLUSIONS

IgG values increase with age. Children with a greater IgG value at the beginning of treatment reached higher PEF values after same. It is not known if the results would be similar with another type of treatment and the way in which IgG influences the results. What appears to be confirmed by available studies is that this relation is found in a group of small children, the aim of our study.

Use of OM-85 BV in children suffering from recurrent respiratory tract infections and subnormal IgG subclass levels

BACKGROUND

Recurrent acute respiratory tract infections (RARTIs) in children are related to IgG subclass deficiencies. The aim of the trial was to evaluate the effect of OM-85 BV in the number of RARTIs as well as in the IgG subclass levels.

METHODS

This was a randomized, double-blind, placebo-controlled clinical trial. Patients of ages three to six years, having three or more documented ARTIs during the last six months with subnormal IgG subclass levels were included. Patients took either one capsule of OM-85 BV (3.5 mg) or placebo orally every day for ten consecutive days per month during three consecutive months. Patients were followed three further months without drug intake. IgG subclass levels were determined before and after treatment.

RESULTS

IgG4 levels diminished after the OM-85 BV treatment (-3 [-8.0, -1.0] median difference [95 % CI] p < 0.05 by Wilcoxon test). No other significant changes in IgG subclasses were observed. After six months the patients in the OM-85 BV group (n = 20) experienced 2.8 1.4 (mean SD) ARTIs, while the patients in the placebo group (n = 20) suffered 5.2 1.5 ARTIs (-2.4 [3.3, -1.5] mean difference [95 % CI] p < 0.001 by Student's t test). Three patients with OM-85 BV had gastrointestinal events related to drug administration, as well as three placebo patients.

CONCLUSION

This study demonstrated the clinical benefit of OM-85 BV in patients suffering from RARTIs and subnormal levels of IgG subclasses. This trial opens new perspectives in the research of the mechanism of action of OM-85 BV.

Immunostimulation with OM-85 in children with recurrent infections of the upper respiratory tract: a double-blind, placebo-controlled multicenter study

OBJECTIVE

Recurrent upper respiratory tract infections (URTIs) are common illnesses in young children. As the immunoactive bacterial extract OM-85 has been shown to prevent these infections in both adults and children, the aim of the present trial was to investigate further its efficacy and safety in infection-prone children.

METHODS

This is a randomized, double-blind, placebo-controlled, multicenter study with OM-85 in 232 patients aged 36 to 96 months with recurrent URTIs. Treatment was one capsule daily during month 1 and during 10 days in months 3 to 5. URTI was defined by the presence of at least two of the following: rhinitis, pharyngitis, cough, hoarseness, temperature > or = 38.5 degrees C, or URTI-related prescription of an antibiotic.

RESULTS

OM-85-treated patients had a lower rate of URTIs (p < 0.05). The cumulated difference in URTIs between the two groups reached - 0.40 URTIs per patient in 6 months, corresponding to a 16% reduction in the active-treatment group with respect to placebo. The largest difference was observed in the patients having had three or more URTIs during the study period; odds ratios for three or more URTIs were 0.51 (95% confidence interval, 0.29 to 0.91) and 0.65 (95% confidence interval, 0.37 to 1.11) after 5 months and 6 months, respectively. The difference between OM-85 and placebo was independent of age but was more important in patients reporting a larger number of URTIs in the previous year. Patients' global assessment showed improvement in comparison to the previous season in the majority of the cases (OM-85, 78.4% of cases; placebo, 75.5%); however, there were more cases reporting worsening with placebo (6.4% vs 0.9%; p = 0.05).

CONCLUSIONS

OM-85 treatment significantly reduced the rate of URTIs, particularly in children with a history of frequent URTIs. Safety and tolerance of test medication were good, comparable to placebo.

Evaluation of the relevance of humoral immunodeficiencies in a pediatric population affected by recurrent infections

Recurrent infections are a common cause of morbidity in childhood. Several reports have associated this condition to low levels of IgA and IgG subclasses and/or lack of specific antipolysaccharide antibody response, although the relevance of these defects in terms of prognosis and therapeutic approach is still unclear. The aim of our study was to determine the frequency and the clinical relevance of humoral immunodeficiency (HID) other than hypogammaglobulinemia in children affected by recurrent infections. We recruited 67 pediatric patients affected by recurrent infections. Serum IgG, IgA, IgM, IgG2, IgG3, and specific anti-Haemophilus influenzae (anti-Hib) antibodies were determined. Thirty-seven out of 67 patients showed antibody defects (55%). IgA deficiency was observed in 21 out of 67 patients (31%), followed by IgG2 (18%), IgG3 (15%) and IgM (6%) defects. Anti-Hib deficiency was present in three out of 44 patients (7%). A tendency for a higher occurrence of pneumonia and otitis, although not statistically significant (p > 0.05), was observed in HID patients compared to children with normal humoral function. No statistical difference as to the frequency of mild infections (URI) was found between HID and non-HID patients. We therefore suggest that the therapeutic program is based on the clinical status of the patients. Long-term follow-up with repeated determinations of antibody levels is crucial, however, to detect those defects that might evolve into more complex immunodeficiencies.

Heterogeneity of humoral immune abnormalities in children with Nijmegen breakage syndrome: an 8-year follow-up study in a single centre

During an 8-year period of observation, defects of immune responses were characterized and monitored in 40 of 50 Polish children with Nijmegen breakage syndrome referred to the Children's Memorial Health Institute in Warsaw. The following parameters were determined at diagnosis: (1) concentrations of serum IgM, IgG, IgA; (2) concentrations of IgG subclasses; and (3) lymphocyte subpopulations. In addition, naturally acquired specific antibodies against Streptococcus pneumoniae were determined in 20 patients with a history of recurrent respiratory infections. During follow-up, total serum immunoglobulins and IgG subclasses were monitored systematically in 17 patients who did not receive immunomodulatory therapy. Moreover, anti-HBs antibody response was measured after vaccination of 20 children against HBV. We found that the immune deficiency in NBS is profound, highly variable, with a tendency to progress over time. Systematic monitoring of the humoral response, despite good clinical condition, is essential for early medical intervention.

Immunoglobulin G subclass concentrations and infections in children and adolescents with severe asthma

It was the aim of this study to investigate possible dysfunctions of the humoral immune system in asthmatic children with frequent respiratory infections. Forty-one severe asthmatics (7-15 years of age), classified according to the Second Brazilian Consensus in Asthma (1998), were divided into two groups: group I (n = 12) had recurrent respiratory infections; and group II (n = 29) were without recurrent respiratory infections. Immunoglobulin (Ig)G, IgA and IgM levels (nephelometry), and IgE (radioimmunoassay) and IgG subclasses (enzyme-linked immunosorbent assay), were evaluated using standard methods. Asthmatics with recurrent infections presented with worse clinical evolution, an increased number of hospital admissions, and a higher need of medication than the children without recurrent infections. There were no significant differences between the mean values of IgG, IgA or IgM levels, or IgE or IgG subclasses, in patients of both groups. A complete IgA deficiency was detected in two patients of group I (one was associated with IgG subclass deficiency). Deficiency of one or more IgG subclasses was verified in eight of 12 (66%) children from group I and in 16/29 (55%) from group II. The following deficiencies were found in both groups: IgG3 (10/41), IgG4 (three of 41), IgG2 (two of 41), IgG1 (one of 41), IgG3-IgG4 (four of 41), IgG1-IgG3 (two of 41), and IgG1-IgG3-IgG4 (one of 41). There were a higher proportion of children with low IgG4 levels in group I than in group II (p = 0.01). To conclude, IgA and IgG subclass deficiencies were detected in both severely asthmatic groups, with a predominance of IgG3 subclass deficiency. However, low IgG subclass levels appear not to be a suitable predictor of the development of infections in asthmatic children.

A hampered chemoattractant-induced cytoskeletal rearrangement in granulocytes of patients with unexplained severe chronic and relapsing infections of the upper and lower airways. In vitro restoration by G-CSF exposure

Granulocytes play a major role in host defense against bacterial infections. Severe inborn defects in granulocyte function are associated with fulminant bacterial infections in early childhood. Subtle disturbances in granulocyte function might contribute to an enhanced susceptibility to bacterial infections in adulthood. We investigated chemoattractant (N-formyl-methionyl-leucyl-phenylalanine, fMLP and casein) induced cytoskeletal rearrangements (polarization) of blood granulocytes in 77 adults with chronic and recurrent therapy-resistant infections of the upper and lower airways. These infections could not be explained by B- and/or T-cell defects or local anatomic abnormalities. Besides polarization, chemotaxis of blood granulocytes was measured in 33 patients, as well as granulocyte superoxide production in eight patients. The chemoattractant-induced cytoskeletal rearrangement in patient blood granulocytes was significantly lower as compared to healthy control values with both fMLP and casein as stimuli. About two-thirds of the patients showed a defective polarization response to fMLP. Granulocyte colony-stimulating factor (G-CSF) when added in vitro corrected the defective polarization responses; responses in the normal range were not enhanced. The chemotactic motility of patient blood granulocytes was also slightly, but significantly lowered. However, it did not correlate to the lowered polarization. Granulocyte superoxide production was comparable in patients and in healthy controls. Our data thus show that subtle abnormalities in chemoattractant-induced cytoskeletal and motile function of blood granulocytes are frequent in patients with severe therapy-refractory bacterial infections of the upper and lower airways.

Serum immunoglobulins and immunoglobulin G subclasses with recurrent wheezing

In this study serum immunoglobulins (Ig) and IgG subclasses were measured in 42 patients (ranging 9 month-6 year) with recurrent wheezing and in 37 healthy children determined the relationship between serum Igs and recurrent wheezing. Patients were divided into two groups according to the age [9 month-2 year (n: 15), and 2-6 year (n: 27)]. In the patients placed in 9-24 month age group, serum IgG4 level was found to be lower than controls (p < 0.05). But there was not a significant difference in mean serum concentrations of total IgG, IgA, IgM, IgE, IgG1, IgG2 and IgG3 subclasses between the groups (P > 0.05). In the 25 month-6 year age group the mean IgE level was increased compared to the control while IgG3 and IgG4 levels were decreased (p < 0.05). On the other hand, in the 9-24 month age group there was no significant difference between the patients and controls for IgG subclasses deficiency (P > 0.05). However, significant difference in IgG subclasses deficiency was present between the patients and controls in the 25 month-6 year group (P < 0.001). In conclusion, our findings suggest that wheezing in childhood may be associated with low IgG3 and/or IgG4, and in older children high IgE level may be a part of pathogenetic mechanism in patients with recurrent wheezing.

Clinical and immunological evaluation of patients with mild IgG1 deficiency

Serum IgG subclass concentrations were determined in patients visiting, the pulmonology out-patient clinic with chronic respiratory tract problems. A total of 24 patients with a serum IgG1 concentration < 4.9 g/l (i.e. below the reference range) and normal values for IgG2, IgM and IgA were included. Patients with a selective IgG1 deficiency were vaccinated with a 23-valent pneumococcal polysaccharide vaccine. There were nine patients with a poor antibody response to pneumococcal capsular polysaccharide antigens. Responsiveness to protein antigens was intact in all patients. Patients with pneumonia showed a significantly lower anti-polysaccharide response in the IgG2 subclass than patients without pneumonia. Patients with recurrent sinusitis showed a significantly lower response in the IgA isotype after vaccination with pneumococcal polysaccharide vaccine compared with non-sinusitis patients. It can be concluded that patients with recurrent sinopulmonary infections and a mild IgG1 subclass deficiency have an impaired IgG1 anti-polysaccharide response, which can extend to decreased IgG2 and IgA anti-polysaccharide responses.

Clearance of Pseudomonas aeruginosa from the murine gastrointestinal tract is effectively mediated by O-antigen-specific circulating antibodies

The colonization of mucosal surfaces by Pseudomonas aeruginosa can lead to local or disseminated disease. Secretory immunoglobulin A (IgA) has been assumed to be responsible for preventing mucosal colonization by interfering with the binding of bacterial ligands to epithelial surface receptors. However, the efficacy of this mechanism of immunity derives little actual support from in vivo experiments. In an investigation of the role of local and systemic immunization strategies in reducing colonization of the gastrointestinal tract of mice by P. aeruginosa, the bacterial antigens that were potential targets for immune effectors promoting mucosal clearance were identified. Levels of gastrointestinal colonization were reduced when immunity to homologous O antigens, but not that to pili or flagella, was elicited. Oral vaccination with attenuated Salmonella typhimurium expressing P. aeruginosa serogroup O11 antigen elicited mucosal and serum IgA antibodies and serum IgG antibodies specific for the recombinant antigen. Oral challenge of immunized mice with P. aeruginosa serogroup O11 demonstrated protection against gastrointestinal colonization. Intraperitoneal immunization with a serogroup O11 high-molecular-weight O-polysaccharide antigen elicited only serum IgG and IgM antibodies yet was as effective as oral vaccination in protecting mice against gastrointestinal colonization. This finding was confirmed by the demonstration that intraperitoneal immunization with purified lipopolysaccharide was also protective against mucosal surface colonization. These results call into question the need for local immune effectors, particularly secretory IgA, directed at bacterial ligands for epithelial surface components, in protecting a mucosal surface from bacterial challenge.

Effectiveness of thymostimulin and study of lymphocyte-dependent antibacterial activity in children with recurrent respiratory infections

Recurrent respiratory infections (RRI) consist of more relapsing acute respiratory infections than the ones expected for the age [> 6 acute respiratory tract infections (RTI) per year if age is > 3 years, and > 8 acute RTI per year if age is < 3 years]. Concerning the pathogenesis of RRI, several investigations report the important role of environmental factors, early socialization and immunological dysfunctions, such as lymphocyte subpopulations alterations, IgG subclass deficiency and phagocytosis and/or opsonization deficit during acute infections. In this framework, we have studied the lymphocyte-dependent antibacterial activity (ABA) among 121 children affected by RRI. Results show a statistically significant alteration of this function in 38 children (31.4%): 19 of them exhibited an absent ABA (group 1), while in the others same function was reduced (group 2). A bovine thymic extract, thymostimulin, was administered to both groups by intramuscular injections (1 mg/kg) for a 3 month cycle. At the end of therapy we observed a statistical significant rise of ABA only in group 1 and among children aged > 3 years. Among the same patients, 33 children (86.8%) improved in terms of reduction of clinical score and better results were seen among children aged > 3 years. These data emphasize the beneficial role of thymostimulin in RRI-affected children, suggesting a transient immaturity of the immune system as one of the possible pathogenetic factor.